Soft tube stretcher

ABSTRACT

A stretcher device for use with soft tubing of the type used on control systems having tubing such as hydraulic or pneumatic tubing or the like. The stretcher may be easily carried by the pipe fitter and may be quickly and easily used to stretch the soft tubing to the desired degree of straightness and length. The stretcher has a means for holding the soft tubing and also means for anchoring the stretcher to a chain which is incorporated with the stretcher. Also disclosed is a method for stretching the soft tubing using the stretcher disclosed.

United States Patent 11 1 Dickerson [451 Feb. 5, 1974 lnventor:

Filed:

Appl. No.: 295,105

SOFT TUBE STRETCHER James C. Dickerson, Rt. 5, Box 181,

West Monroe, La. 71291 Oct. 5, 1972 US. Cl 72/367, 72/458, 72/705,

Int. Cl 821d 3/12 Field of Search 72/458, 367, 369, 705;

References Cited UNITED STATES PATENTS Baynes Springer Cox Williams 254/78 2,704,200 3/1955 Call 254/78 Primary Examiner-Charles W. Lanham Assistant ExaminerGene P. Crosby Attorney, Agent, or FirmNorvell E. Von Behren [5 7] ABSTRACT A stretcher device for use with soft tubing of the type used on control systems having tubing such as hydraulic or pneumatic tubing or the like. The stretcher may be easily carried by the pipe fitter and may be quickly and easily used to stretch the soft tubing to the desired degree of straightness and length. The stretcher has a means for holding the soft tubing and also means for anchoring the stretcher to a chain which is incorporated with the stretcher. Also disclosed is a method for stretching the soft tubing using the stretcher disclosed.

6 Claims, 4 Drawing Figures SOFT TUBE STRETCHER BACKGROUND OF THE INVENTION This invention relates generally to stretching devices and particularly ,to a new and novel soft tubing stretcher for use on thin wall control tubing of the type used on pneumatic or hydraulic control systems or the like.

Control devices for industrial systems are generally inter-connected by a vast network of tubing through which is carried the media by which the control is activated such as air, vacuum and/or a hydraulic fluid such as oil or water or the like. The tubing generally used is a thin wall tubing, usually formed of soft copper or aluminum, and has a small outside diameter ranging from one-eighth of an inch upward depending upon the control system for which it was designed.

Prior to the invention'of the subject tube stretcher, there were no suitable commercial stretchers on the market and the pipe fitter was left to his own. resources when he had to stretch the soft tubing which was supplied to the installer coiled in large coils as received from the tubing supplier. In order to mount the control tubing in the desired positions with a neat appearance, it was necessary to stretch the tubing out of the coiled form into a straight length that could be easily erected on the job site without distortions, curves and .bends or the like.

Prior to the subject invention, the stretching of the tubing usually involved tying one end of the coil to a nearby existing pipe and physically rolling the coil out in a straight line with the pipe fitter then placing his foot over the tubing at the other end and pulling the same other end upwards, using his foot as a means of holding the tubing down, until the desired degree of straightness was obtained. As an alternate to this method, the other end of the tubing would be pulled around a nearby pipe or fixed object while the first end was also tied to another fixed object. This method and the before described method, while stretching the tubing somewhat satisfactorily, often resulted in the tubing being completely stretched to the desired length but having flat spots occasioned by pulling the tubing around the pipe or the foot of the pipe fitter.

A search of the prior art revealed various devices for use in stretching various other objects but none having the new and novel features of the subject invention. For example, various devices have been patented for stretching wire such as barbed wire and these are typified in the U.S. Pat. No. 371,514, issued to W. A. Murray on Oct. 11, 1887; U.S. Pat. No. 723,244, issued to CL Cox et al. on Mar. 24, 1903; and U.S. Pat. No. 1,024,223, issued to J. Pitre on Apr. 23, 1912. All these patentsteach the use of an elongated rod or bar in conjunction with other features not pertinent to applicants invention for the purpose of stretching the wire.

Similarly the U.S. Pat. No. 1,453,874, issued to I-I.F. Hotchkiss on May 1, I923 teaches the same basic principle in use in stretching automobile tire chains to fasten them around an automotive tire.

The same principle using a red as a fulcrum has also been applied to other art such as the steel erecting art as typified by the U.S. Pat. No. 1,317,145, issued to T. Skantz on Sept. 23, 1919 and the railroad art as shown in the U.S. Pat. No. 640,105, issued to BE. Crowell on Dec. 26, 1899.

A somewhat different applicationof this principle is shown in the U.S. Pat. No. 1,215,180, issued to A. J. Morrow on Feb. 6, 1917 wherein there is provided a stevedores peavey using the principle to provide the stevedore with a fulcrum bar which he can use for heavy lifts or heavy pulls with a minimum of force.

While all of these prior art devices use the same basic principle of a fulcrum to minimize the applied forces necessary to do a given job, none have utilized the new and unusual design concepts taught by the subject invention and as applied to the basic fulcrum to accomplish the results provided for by the applicant's disclosure.

SUMMARY OF THE INVENTION In order to overcome the problems encountered in the prior art devices and to utilize the basic principle of a fulcrum with new and novel important embelishments, there has been provided by the subject invention a new and novel soft tubing stretcher using the fulcrum principle which has means incorporated on the stretcher to removably anchor the fulcrum on a chain which is also incorporated with the fulcrum rod. With the use of the removable anchor means, the stretcher may be quickly and easily walked along the chain to easily stretch the tubing to the .desired degree of straightness and length. The stretcher also has formed thereon simple means for quickly and easily attaching and detaching the stretcher from the tubing being stretched. This means is also used to hold the chain in place around the stretcher whenever the stretcher is not being used thereby allowing it to be easily carried in the tool box of the pipe fitter.

Accordingly it is an object of the invention to provide a new and novel soft tubing stretcher which may be easily installed on the job site to stretch soft tubing.

Another object of the invention is to provide a simple soft tubing stretcher which has a minimum of parts which are all fixedly attached to the stretcher and which can be quickly used to stretch the soft tubing to the desired degree of straightness.

Still'another object is to provide a novel soft tube stretcher that-can easily be carried on the job site by the pipe fitter of the tubing.

Yet another object of the invention is to provide a new and novel soft tubing stretcher that can easily be used to walk along a self-contained chain while stretching the tubing without deforming the tubing as had been the previous practice.

Still yet another object of the invention is to provide a new and novel method of stretching soft tubing using the new and novel stretcher of the invention.

This object and other advantages of the invention will become apparent from a reading of the description of the preferred embodiment and from a study of the drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a side view of the new and novel tubing stretcher of the invention showing it being used to stretch a piece of soft tubing;

FIG. 2 is a partial side section view of the end of the tubing stretcher taken along line 2-2 of FIG. 1;

FIG. 3 is a side view of the tubing stretcher showing it not in condition for easy storage in the users tool box; and

FIG. 4 is a partial side section view of a modification of the end of the tubing stretcher taken along line 2-2 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing in general and in particular to FIG. 1 of the drawing there is shown the new and novel tube stretcher of the invention generally by the numeral and comprises an elongated rod 12 which may be solid or hollow as the case may be. The rod 12 has fixedly attached thereto, by means ofa weld 14 or some other suitable fastening means, a chain 16 which has fixedly attached to the other end thereof, by means well known in the art, a hook 18 or some other suitable fastening means.

The rod 12 also has formed thereon in the central portion thereof means for holding the soft tubing while it is being stretched. The holding means, in the preferred embodiment, comprises an elongated frame member 20 which may be fixedly attached to the rod 12 by means of the weld 22 or by other means well known in the art. The frame 20 has formed therein, in the central portion thereof, a hole 24 having a diameter somewhat larger than the diameter of the soft tubing being stretched.

Formed on the lower end of the rod 12 is an anchoring means for anchoring the lower end of the rod 12 to the chain 16 whenever the device is being utilized as will be described more fully hereinafter. The anchoring means comprises an elongated bifurcated frame member 26 having two branches 28 and 20 defining an elongated slot 32 which has a width, as shown by the arrow 34 in FIG. 2, somewhat larger than the diameter 35 of a single link in the chain 16. The length 36 of the slot 32 is also formed somewhat longer than the height 38 of a single chain link. When formed in this manner, the branches 28 and 30 are temporarily anchored at the point 40 to the link in the chain by being forced against the next succeeding link 42 whenever the device is being used as will be described more fully hereinafter.

When using the tube stretcher, the pipe fitter attaches the soft tubing 44 to the frame 20 by passing the end 46 of the tubing through the hole 24 and bending it back on the tubing 44 as shown in FIG. 1 of the drawing. He also fixedly attaches the hook 18 on the nearest available fixed object 48, such as a pipe or a piece of floor grating. Whenever the nearest fixed object is too large for the open end of the hook 18, he simply can wrap the hook end of the chain around the fixed object and can fasten the hook 18 back on the chain 16 as is well known in the art.

Thereafter the pipe fitter slips the slot 32 over the first free vertical chain link 50 of the chain 16 and applies a force in the direction shown by the arrow 56 thereby stretching the tubing a predetermined amount. Thereafter he removes the device from the chain link 50 and walks it or moves the frame 26 to the next vertical chain link 52 by raising the rod somewhat and pivoting the upper end 57 in the direction shown by the arrow 58 about the hole 24 while keeping the tubing taut. After applying another force in the direction shown by the arrow 56 the pipe fitter repeats the process moving on to the next link 54 and then further length is obtained.

By use of the novel bifurcated frame 26 in combination with the chain, the tubing may be quickly and easily stretched without causing flat spots in the tubing or wasting a large amount of tubing as when using the before-mentioned prior art methods. With the present invention, the only loss in tubing is the small amount of tubing that is bent after being passed through the hole 24 when applying it to the tube stretcher.

As a modification of the basic invention, the bifurcated member 26 could be replaced with a frame 60 having a protuberance 62 formed on its lower portion. With this modification, the pipe fitter would use only the horizontal links 64, 66 and 68, etc., instead of the vertical links 50, 52 and 54 etc. and would temporarily anchor the rod to the chain by inserting the protuberance inside the horizontal links.

When using either the preferred embodiment or the modification, it is understood that the other end of the tubing being stretched is fastened to a nearby fixed object such as a pipe or the like in order to be able to exert the necessary force required to stretch the tubing.

Referring now to FIG. 3 there can be seen how the hole 24 can also function as a means for holding the chain 16 in place whenever the device is being stored. By wrapping the chain 16 around the rod 12 and by inserting the end 70 in the hole 24, the chain 16 will be tightly retained around the rod 12 and the complete device can be easily carried in the pipe fitters tool box without the chain 16 becoming knotted or the hook 18 catching on something in the tool box.

From the above it becomes apparent that there has been provided a new and novel tube stretcher that accomplishes all of the objects and advantages of the invention. Nevertheless it should be apparent that many changes can be made in the parts of the device without departing from the spirit and scope of the invention and the invention is not to be limited to the preferred embodiment which has been given by way of illustration only.

I claim:

1. A soft tubing stretcher comprising:

a. an elongated rod;

b. a chain, fixedly attached at one end of said chain to a portion of said rod;

0. means, fixedly attached to the other end of said chain, for fastening said chain to a fixed object;

d. means formed on the central portion of said rod,

for holding the soft tubing while it is being stretched; and

e. means, formed on one end of said rod, for anchoring said rod along said chain whenever a force is applied to the other end of said rod thereby stretching the soft tubing to a pre-determined length and degree of straightness.

2. The tubing stretcher as defined in claim 1 further comprising said holding means comprising an elongated frame, fixedly attached to said rod and having formed through the central portion thereof a hole having a diameter larger than the diameter of the tubing being stretched.

3. The tubing stretcher as defined in claim 1 further comprising said anchoring means comprising an elongated bifurcated member beingfixedly attached to said rod, the slot formed between the bifurcated legs being wider than the diameter of a chains link and longer than the height of a chain link so that said bifurcated member is easily positioned over a vertical link of said chain and can be removed from said link to be positioned over the next succeeding vertical link.

4. The tubing stretcher as defined in claim 1 further comprising said anchoring means comprising an elongated member fixedly attached to said rod and having an elongated protuberance formed thereon for engaging the horizontal links of said chain.

5. The tubing stretcher as defined in claim 2 further comprising said fastening means comprising a hook having a tip formed thereon and further comprising said hole being formed of a diameter larger than the tip of the hook and said hole functioning as a means for holding the chain in place around the rod whenever the tip of the hook is positioned within the hole.

6. A method of stretching soft tubing comprising the steps of:

a. providing an elongated soft tubing stretcher having formed thereon fastening means, fixedly attached to a chain, and also having formed thereon means for holding the soft tubing and means for anchoring one end of the stretcher to the chain;

b. attaching the soft tubing to the holding means;

0. attaching the chain to the nearest available fixed object by using the fastening means;

(1. attaching the anchoring means to the chain;

e. applying a pre-determined force to one end of the stretcher to stretch the tubing to a pre-determined length and degree of straightness; and

f. removing and repositioning the anchor means to another position on the chain; and

g. successively repeating steps (e) and (f) as required until the tubing has been stretched to the desired length and degree of straightness. 

1. A soft tubing stretcher comprising: a. an elongated rod; b. a chain, fixedly attached at one end of said chain to a portion of said rod; c. means, fixedly attached to the other end of said chain, for fastening said chain to a fixed object; d. means formed on the central portion of said rod, for holding the soft tubing while it is being stretched; and e. means, formed on one end of said rod, for anchoring said rod along said chain whenever a force is applied to the other end of said rod thereby stretching the soft tubing to a predetermined length and degree of straightness.
 2. The tubing stretcher as defined in claim 1 further comprising said holding means comprising an elongated frame, fixedly attached to said rod and having formed through the central portion thereof a hole having a diameter larger than the diameter of the tubing being stretched.
 3. The tubing stretcher as defined in claim 1 further comprising said anchoring means comprising an elongated bifurcated member being fixedly attached to said rod, the slot formed between the bifurcated legs being wider than the diameter of a chain''s link and longer than the height of a chain link so that said bifurcated member is easily positioned over a vertical link of said chain and can be removed from said link to be positioned over the next succeeding vertical link.
 4. The tubing stretcher as defined in claim 1 further comprising said anchoring means comprising an elongated member fixedly attached to said rod and having an elongated protuberance formed thereon for engaging the horizontal links of said chain.
 5. The tubing stretcher as defined in claim 2 further comprising said fastening means comprising a hook having a tip formed thereon and further comprising said hole being formed of a diameter larger than the tip of the hook and said hole functioning as a means for holding the chain in place around the rod whenever the tip of the hook is positioned within the hole.
 6. A method of stretching soft tubing comprising the steps of: a. providing an elongated soft tubing stretcher having formed thereon fastening means, fixedly attached to a chain, and also having formed thereon means for holding the soft tubing and means for anchoring one end of the stretcher to the chain; b. attaching the soft tubing to the holding means; c. attaching the chain to the nearest available fixed object by using the fastening means; d. attaching the anchoring means to the chain; e. applying a pre-determined force to one end of the stretcher to stretch the tubing to a pre-determined length and degree of straightness; and f. removing and repositioning the anchor means to another position on the chain; and g. successively repeating steps (e) and (f) as required until the tubing has been stretched to the desired length and degree of straightness. 